1. Field of the Invention
This invention relates to a door frame and more particularly to a door frame comprised of two unitary door frame members.
2. Description of the Related Art
Door frames traditionally include a pair of vertically disposed side jambs and a head jamb extending across the upper ends of the side jambs. One of the side jambs is usually termed a hinge jamb while the other side jamb is usually termed a latch jamb. The door frame is normally positioned in a door opening formed in a wall surface. Vertical and horizontal trim members are then positioned at the opposite sides of the door frame to cover the gap between the door frame and the door opening. Traditionally, these door frame members are made of wood, aluminum, steel, plastic and/or fiberglass. The members are normally fabricated/manufactured from boards, bent steel plates, extruded aluminum, extruded plastic and/or pultruded fiberglass. All of these methods of manufacture produce straight structural members which must be joined at their junctures. Necessarily, because of the above-described construction of the door frame, joints are present between the side jambs and head jamb, as well as miter joints being present between the vertical and horizontal trim members. Additionally, joints are formed at the juncture of the trim members and the jambs. A wood door is normally hingedly secured to the hinge jamb. The door frame may be sold as a pre-hung door assembly or the door may be installed in the door frame after the door frame has been installed in the door opening.
If the door frame described above is used in a food or meat processing plant, the joints therein present a space in which bacteria may grow and which makes cleaning thereof difficult. Inasmuch as food and meat processing plants are frequently washed or cleaned with corrosive chemicals, the steel door frames and doors secured thereto rapidly deteriorate. However, even stainless steel side jambs and head jambs still have joints therebetween unless the joints are welded and ground smooth. Usually, these joints are the weakest points in the frame and can separate or cause difficulty during installation and, in some cases, open or separate after installation. Further, if separate steel trim members are used, miter joints exist between the vertical and horizontal trim members. Additionally, since wall thicknesses vary, it is necessary to fabricate door frames of varying sizes to accommodate the same.